Zoonosis and meat workers

As part of an ongoing series of articles about the dangers of zoonotic diseases to meatworkers, we have previously dealt with Q Fever.

This article looks at Leptospirosis.

Leptospirosis is one common zoonotic disease that affects cattle and pigs. this article will focus on how it is spread by pigs.

The disease has many forms, some of which can be life threatening. Slaughtermen and labourers are at extremely high risk, but whilst these workers are probably at highest risk, all meat workers are at a significantly higher risk that other members of the public.

How it Spreads
It is introduced into piggeries by the urine of carrier pigs or occasionally rodents and is more prevalent where sows lie in pools of urine or where sows are group housed with open drains.

Diagnosis
Laboratory tests are the only means of positively identifying the bacteria – however chronic leptospirosis will produce small, pale lesions on the kidneys of an infected pig (white spot). In 1998 Australia’s pig health monitoring services reported that over 71,000 pigs examined by them, 4.2% had typical nephritis lesions on their kidneys.(ii)

Health Risk for Workers
Unvaccinated carrier pigs are a serious health risk to piggery and abattoir staff and transport drivers.
Human infection can cause prolonged and severe symptoms similar to those of the ‘flu, together with ongoing fatigue and joint soreness. The fatality rate is less than 1%, however in its serious form, copenhageni, the clinical syndrome is one of acute onset with fever, usually jaundice, malaise, vomiting, prostration muscle pains and head ache.

There may also be renal failure with haematuria, myocarditis, hepatitis or petechial and purpuric haemorrhages.

Leptospirosis is a notifiable disease – associated cases should be investigated to determine the source of infection. (iii)

Unfortunately there is no suitable vaccine for humans.

Compensation
It is because of the potential of leptospirosis outbreaks to reach significant proportions; companies and insurers attempt to play down its significance – presumably because of the cost involved with workers compensation.

It is not uncommon for insurers to claim that a domestic pet caused the infection and to oppose the claim on that basis! It is possible to be infected by a domestic pet, if it has consumed contaminated water – however, for meat workers the balance of probability is that he or she has received the infection in the course of their employment.

The union will approach the Government with a view to introduce laws to help to protect meatworkers.